抄録
Attempts to control sedimentation and convection using a superconducting magnet are introduced. Magneto-Archimedes levitation was applied to protein crystal growth by converting the aqueous protein solution into paramagnetic with the addition of Gd ions. Since the responses of diamagnetic protein crystals and paramagnetic surrounding solution toward a magnetic flux density gradient are opposite to each other, the tendency of the crystals to escape from the magnetic field can be augmented, leading to levitation at the air-solution interface. Navier-Stokes equations were numerically solved in the presence of the magnetic, escaping force. A number of instances were shown in which convection was suppressed by use of a magnetic flux density gradient. Quality improvements of lysozyme crystals grown in a magnetically levitated state were demonstrated by white X-ray topography.